IDELVION

What it is

IDELVION is a recombinant fusion protein linking coagulation factor IX with albumin (albutrepenonacog alfa). The product contains a purified protein produced by recombinant DNA technology, generated by the genetic fusion of recombinant albumin to recombinant coagulation factor IX, with the genetic fusion of the cDNA of human albumin to the cDNA of human coagulation FIX enabling the protein to be produced as a single recombinant protein and assures product homogeneity by avoiding chemical conjugation. IDELVION remains intact in the circulation until FIX is activated, whereupon albumin is cleaved, releasing activated FIX when it is needed for coagulation. IDELVION is a preservative-free, sterile, non-pyrogenic, lyophilised powder to be reconstituted with Water for Injections for intravenous injection. No human or animal-derived proteins are added during any stage of manufacturing or formulation of IDELVION.

Approved indications

IDELVION is indicated in all patients with haemophilia B for: — Routine prophylaxis to prevent or reduce the frequency of bleeding episodes — Control and prevention of bleeding episodes — Control and prevention of bleeding in the perioperative setting

Dosing overview

For routine prophylaxis in patients aged 12 years and older, the recommended dose is 25–40 IU/kg once weekly, with adult and adolescent patients who are well controlled on a 7-day regimen potentially switched to 50–75 IU/kg every 14 days. For paediatric patients under 12 years of age, the recommended dose for routine prophylaxis is 35–50 IU/kg once weekly. Dosing regimens should be adjusted based on individual patient clinical condition and response, and in some cases, especially in younger patients, shorter dosage intervals or higher doses may be necessary depending on individual patient pharmacokinetics, age, bleeding phenotype and physical activity. Treatment should be initiated under the supervision of a physician experienced in the treatment of haemophilia B, and decisions about home treatment should be made by the treating physician with appropriate training provided and use reviewed at intervals.

Key safety warnings

IDELVION must not be mixed with other medicinal products or diluents in the absence of compatibility studies. After reconstitution, the product has demonstrated chemical and physical in-use stability for 8 hours at room temperature, but contains no antimicrobial preservatives, so if not used immediately after reconstitution it should be stored at room temperature and used within 4 hours.

Regulatory history

IDELVION was first registered on the ARTG on 20 September 2016, initially with five strengths: 250 IU, 500 IU, 1000 IU, and 2000 IU presentations, followed by a 3500 IU presentation registered on 19 November 2020. The TGA approved IDELVION for the treatment and prophylaxis of bleeding in patients with haemophilia B, based on a favourable risk-benefit profile supported by the clinical program demonstrating the drug's efficacy and safety. Its prolonged half-life, achieved by fusion to recombinant human albumin, allows for less frequent dosing compared to conventional Factor IX products.